Hi all,
I started making a list of known and unknown changes with some Greatest Hits (GH) versions of PS1 games. Why? Well, either my Google Fu sucks (possible..) or there just aren't any concise, easily found sources (unlike CRTGAMER's excellent PS2 guide on this).
Why focus on GH? Although there were some cases where revisions were added to some black label copies, GH versions are guaranteed to have them.
I started by reaching out to the Reddit community, then I also added games all games reported by redump.org as having different versions on their GH releases. The Google Sheet is here. As you may see, for the majority of games, I do not currently have any information for what was changed. I think it's fair to assume bug fixes and typos are most likely.
Now, I'm not here just to share but make a simple request. If y'all have any details/corrections regarding notable changes to any of these releases, please share! It would be greatly appreciated!